How to Write a Broadway Musical. The Broadway musical is a great American theatrical tradition that has been wildly popular for over a century. If your ambition is to write a Broadway musical, you are in the brilliant company or George Gershwin, Rogers and Hammerstein and Andrew Lloyd Webber.
Decide whether to go it alone or collaborate. Some musicals are primarily the creation of a single genius. Others are the brainchildren of a creative partnership. Collaborators can include a playwright, a lyricist, a composer, a set designer and others.
Come up with a concept. Musicals are essentially storytelling through song. You can rewrite an old story in a new way. For example, "Camelot" retells the King Arthur legend and "West Side Story" revisions "Romeo and Juliet". You can also write a completely new tale drawn from history, autobiography or fantasy. There are no limits, and fact or fiction can be your inspiration.
Write a script. Invent compelling characters ranging from heroes to villains to comic relief to narrators. Imagine situations that will challenge these people and decide whether they triumph or fail. Remember that comedy and tragedy are both fair game in a Broadway musical and that the right blend of both is a mark of many acclaimed productions.
Compose an original score. The joys and sorrows of the characters suggest moods, styles and lyrics. While the "show tune" is generally considered a style unto itself, it can be argued that the genre of the musical includes both rock operas like "Tommy" and operettas like "The New Moon".
Follow the conventions of the Broadway musical such as the overture, opening number and finale. The first song of the show establishes the story line and introduces at least one of the characters. A classic example is Marian high in the Alps singing "The Sound of Music". The love duet is another time-honored tradition. Think of Carousel's "If I Loved You". Humorous songs like "Me Mother's Wedding Day" in Brigadoon are light, fun and engaging. Songs develop the characters, engage the audience and help to tell the story.
Vary styles, themes and moods as you write the musical numbers. One criticism often leveled at Broadway musicals is their tendency toward repetition. Use reprises of instrumental and vocal numbers deliberately to evoke recurring events, ideas and emotions. Use different keys, instruments or singers to create a fresh sound and feel.
Find a backer. The road leading to the Great White Way is paved with green dollar bills.